Find all points of discontinuity of $f$, where $f$fined by $ f(x) = \left\{ \begin{array} {1 1} x^{10} -1 ,& \quad\text{ if $ x $ \(\leq 1\)}\\ x^2,& \quad \text{if $x$ > 1}\\ \end{array} \right. $

Question

$\begin{array}{1 1} \text{Point of discontinuity is x=1} \\ \text{Point of discontinuity is x=-1} \\ \text{Points of discontinuity are all x<1} \\ \text{Points of discontinuity are all x > 1}\end{array} $